| Tosanoides aphrodite|
Pinheiro, Rocha & Rocha, 2018
During a recent expedition to St. Paul’s Rocks, Atlantic Ocean, a distinctive and previously unknown species of Anthiadinae was collected at a depth of 120 m. A genetic analysis indicated the undescribed species is a member of the genus Tosanoides, which was only known to occur in the Pacific Ocean. This new taxon is distinguishable from all other Tosanoides species by the following combination of characters: soft dorsal fin rays 15–16; anal fin rays 9; ventral scale rows 9–10; last dorsal spine the longest (instead first through fourth). Here Tosanoides aphrodite sp. n. is described and illustrated, only known from St. Paul’s Rocks.
Keywords: Brazil, coral reefs, deep reefs, fish endemism, oceanic island, rebreather diving
|Figure 3. Fresh specimens of Tosanoides aphrodite sp. n. collected in St. Paul’s Rocks, Brazil. A Male B Female. Photographs by LA Rocha.|
Tosanoides aphrodite sp. n.
Diagnosis: The new species differs from all other Anthiadinae by the following combination of characters: Dorsal-fin spines X; last dorsal spine the longest, 1.8–2.2 in head length; dorsal-fin rays 15–16; 7th dorsal ray the longest, 2.65–2.80 in head length; anal-fin rays 9; pored lateral-line scales 32–35; ventral scale rows 9–10; body slender and compressed, greatest depth 2.96–3.18 in SL, and the width 1.77–2.09 in depth. Our phylogenetic analysis shows the new species belongs to Tosanoides Kamohara 1953, from which it differs of the other known species by: a divergence of at least 12.35% at the cytochrome oxidase I gene, last dorsal spine the longest (instead first through fourth), fewer dorsal-fin rays (15–16 vs. 16–17), and more anal-fin rays (9 vs. 8 in the other Tosanoides).
|Figure 4. Tosanoides aphrodite sp. n. in its natural environment, photographed at a depth of 120 m in St. Paul’s Rocks, Brazil. Photograph by LA Rocha.|
Etymology: The name “aphrodite” refers to the ancient Greek goddess of love and beauty. While we were collecting the Aphrodite anthias, a large Six-gill shark (Hexanchus griseus) came very close to both of us (HTP and LAR), but that didn’t divert our attention from the new exquisitely beautiful species, and we never even saw the shark (youtu.be/pSZrmoEwR0Q). The beauty of the Aphrodite anthias enchanted us during its discovery much like Aphrodite’s beauty enchanted ancient Greek gods.
Distribution and habitat: Tosanoides aphrodite is only known from Saint Paul’s Rocks, off Brazil. It was found on mesophotic coral ecosystems of the island, observed between 100 and 130 m depth while rebreather diving, and a single observation at 260 m depth, taken from a submersible dive. The species inhabits small crevices of complex rocky reefs (Figure 4). The ambient seawater temperature at the collecting depth (~ 120 m) varied between 13 and 15 °C during the two-week period we stayed in the area.
Hudson T. Pinheiro, Claudia Rocha and Luiz A. Rocha. 2018. Tosanoides aphrodite, A New Species from Mesophotic Coral Ecosystems of St. Paul’s Rocks, Mid Atlantic Ridge (Perciformes, Serranidae, Anthiadinae). ZooKeys. 786: 105-115. DOI: 10.3897/zookeys.786.27382